Tubular roller

ABSTRACT

A tubular roller has a circumferential tubular wall provided at its opposite ends with circumferentially offset first cutouts and projections located between adjacent ones of the cutouts. The roller further has two end walls located at the opposite ends and rigidly connected with the tubular wall. The end walls each have circumferentially offset second projections received in the first recesses of the tubular wall, and second recesses which accommodate the first projections of the tubular wall.

United States Patent Specth Feb. 26, 1974 TUBULAR ROLLER 501,897 7/1893 Pendleton 29/123 x [75] Inventor: Dieter specth, Dhuenn/Rhineland, 3,416,638 12/1968 Buck 29/1295 X Germany Primary ExaminerAlfred R. Guest [73] Assignee: Hans Vom Stein 0HG, A A t h l S St Dhuenn/Rhineland Germany orney, gen or zrm 1c ae r1 er [22] Filed: Oct. 16, 1972 [21] Appl. No.: 297,987 [57] ABSTRACT A tubular roller has a circumferential tubular wall pro- [30] Foreign Appficafion Priority Data vided at its opposite ends with circumferentially offset Feb 4 1972 German P 22 05 242 2 first cutouts and pro ections located between ad acent y ones of the cutouts. The roller further has two end walls located at the opposite ends and rigidly con- '3 nected with the tubular wall. The end walls each have circumferentially offset second projections received in [58] Fleld of Search 29/] 1 16 1295 the first recesses of the tubular wall, and second reces- 5 6] References Cited zelsl ghvlvcglil accommodate the first pro ections of the [tu- UNITED STATES PATENTS 1,255,661 2/1918 Stewart 29/123 X 7 Claims, 2 Drawing Figures if \N 31 1 TUBULAR ROLLER The present invention relates, to a roller, and morev particularly to a tubular roller. Still more particularly the invention relates to a tubular roller which can be used in roller conveyors, as reversing and supporting rollers for conveyor belts and for other applications. Rollers used in such applications usually have a tubu lar.cireumferential wall and two end walls which are insertedinto theopen ends of the tubular ,wall and are mounted therein. The shaft or. axis about which the rol} ler rotates is secured in these end walls either fixedly or by means of bearings. A variety of different constructions has been proposed in the art for such rollers, including the bonding, welding,press fitting and the like I 4 v Another proposal in the prior art for connecting the of the errd walls to the tubular wall.

relative to the tubular walls as well as against relative v angular movement. 7

A difficultywhich has long' been experienced in'this field has been'that a lasting sturdy and rigid connection between the'end walls and the tubular circumferential wall is very difficult to obtain; Of course, it is possible to form-an abutmentshoulder either on the inside of the tubulaf wall adjacent the respective open end thereof; against-which the end wall can abut, or'else to form such an abutment shoulder onthe respective end wall and 'have the axial end of f the tubular wall abut ag'ainstit. This does prevent relative axial displacement of the end-wall and tubular wall, although at the cost of the relatively expensive production of such shoulder. Over a prolonged period of time during which such rollers are in operation, and if the rollers are subjected to heavy loads, it has been found, however, that a really reliable and permanent connection of the tubular wall and the end walls against relative rotational or angular displacement is almost impossible to obtain. A prerequisite: for this would be to precisely fit the end walls into the tubular wall, and this in turn would require .such'exacting tolerances in the manufacture of these .wallsas to make the rollers-prohibitively expensive. lfthe. circumferential wall and the end walls are of different materials, which is quite often the case in such rollers, for instance if the circumferential wall is metal and-the end walls are of synthetic plastic, than the connection between the circumferential walland the end walls will quite quickly become loosened'due to differential coefficients of thermal expansion and contraction of the two materials.

In addition, due to the inevitable relative flexing movement occurring between end walls and tubular wall when substantial stresses are applied to the roller,.:

the connection established between the walls is loos--,

ened so that a relative rotational displacement between more or less continuous use.

In addition, it is particularly important that in the case of large rollers of this type, or of rollers which are subjected to significant stresses, or which are not only subjected to thosewstressesbut are also large in dimen-" sion, the circumferential tubular wall has relatively significant wall thickness. In a roller of the type. just, mentioned, such wall thickness is a prerequisite for the rolr-i ler to be ableto withstand the forces acting upon it. However, such. significant wall thickness then makes thedeformation of the material at the axial ends of the tubular wall into, connecting engagement with the end walls rather diff cult andqexpensive. Evidently, there fore, further improvements in this field are desirable. It is a general object of the present invention to provide such improvements. LMOI'Q particularly, it is an object of the invention 'to providesan improved tubular roller of the, type here under discussion, which is not possessed of the afore,-

mentioned disadvantagesof the prior art.

Another objectof; the invention is to provide such a tubularroller in which the end walls. can be readilyand relatively simply secured tothe opposite axialends of the,tubula r.circumferential wall; both against axialand rotational displacement relative to the latter,'and inwhieh-suchsecuring can be effected in .;such a manner asrto be reliableand permanent even under the influ-= ence of high stresses and temperature fluctuationsacting upon the roller.

Anotherobject of the invention is to provide ,such an improved roller in which the dimensional tolerances to which the various walls must be produced in order to be ableto effect the connection according to the 'present invention, can. be, such ,thatthe components can be produced economically, that is without excessively ehaexn nses. I

in; pursuanee ofthembove objects, and others which willbecomeapparengone feature of the invention resides in a tubular roller, which is particularly though not exclusively suitable for conveyors and the like, and which comprises, briefly stated, a circumferentialtubular wallhaving at its opposite endscircumferentially,

offset first cutouts, and projections located bet ween ad jacent onesof the cutouts. Endlwalls are provided, beinglocated at the opposite ends of the tubular wall and being rigidly'connected with the latter. The end walls each have circumferentially offset second projec- In other words, the projections and recesses of the tubular. wall mesh and inter-engage with the'projectionsa.

and recesses of the respective end walls. Thisinterengagement prevents relative axial-displacement of the walls andrelative rotational displacement thereof, even when aroller so constructed is in continuous operation and is subjected to high loads and significant temperal ture fluctuations.

The rolling deformation of the circumferential wall at theopposite axial ends to establish the final connection. with the end walls-need thus, of course, take place only over circumferentially spaced portions of the tubular wall, thus being considerably simpler to carry out'than what is knownfrom the prior art and requiring less-.

force than waspreviously necessary. For this reason, it

It is advantageous if the circumferential dimension of all recesses and projections is identical, and it is further,

advantageous if thelateral flanks bounding the projections at the opposite axial ends of the tubular circumferential wall, aswell as those bounding the projections on the end walls, are located in radial planes of the roller, that is in planes passing through the central longitudinal axis of the roller.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following. description of specific embodiments when read in connection with the accompanying drawing.

FIG. 1 is a fragmentary axial section through one end portion of the roller according to the present invention;

and

FIG. 2 is a perspective exploded view of the components shown in FIG. 1, prior to their assembly.

Discussing the drawing now in detail it will beseen that the roller illustrated in FIGS. 1 and 2 has a tubular circumferential wall which may be of metallic material or of synthetic plastic material. Only one end portion 12 of the wall 10 has been illustrated, together with its associated end wall 14. It is to be understood, however, that the opposite end portion of the wall 10, together with its associated end wall, will be configurated in the same manner as the end portionand the end wall which have been shown in the drawing.

Further, it is emphasized that although the roller illustrated is shown as being tumably mounted on a shaft 13, the invention is quite clearly equally applicable if the roller is mounted on the shaft 13 so that it can retate with the same but not relative to the same. In other words, the manner in which the roller is associated with the shaft 13 is of no importance for the purposes of the invention.

The end portion 12 of the tubularwalllt) is provided with circumferentially alternating recesses 40 and projections 41. In other words, the projections 41 are the result of the formation of the recesses or cutouts 40. According to the illustrated embodiment which is not, however, to be considered limiting, the circumferential length of the recesses 40 as well as of the projections 41 is identical.

The end wall 14 has an inner annular portion or hub 15 which may be of synthetic plastic material and which is mounted on the shaft 13. The inner race 17 of a ball bearing is accommodated in the annular hub 15 between a wall 20 and a projecting nose 21. The outer race 18 of the ball bearing surrounds the inner race and the anti-friction bearing balls are designated with reference numeral 19. Race 18 abuts'against the inner side 'of an outer annulus 26 the outer side of which is provided with a plurality of circumferentially spaced teeth 30 extending in parallelism with the axis of the annulus 26.

A ring 27 is provided having on its inner side teeth corresponding to and engaging the teeth 30 of the annulus 26; the outer side of the ring 27 (which latter is press fitted into the end portion 12 of the tubular wall 10) abuts the inner circumferential surface of the end portion 12. A projecting nose 29 of the annulus 26 retains a ring 28 which is intended to prevent the intrusion of dust or other contaminants, and which is main-' tained by the nose 29 in abutment with the inner side of the races 17 and 18. A further ring 32 of angled profile (see FIG. 1) has a nose 31 which extends into a correspondingly configurated groove of the annulus 26,

being receivedtherein with a snap action. The radially extendingportion of the ring 32 is abutted on its inner side by another angular-profile sealing ring 33 which is .biased against it by a spring 34 as shown. The space between the rings 32 and 33 may advantageously be filled with a lubricant, such as grease, so that the necessary lubrication is assured whereas on the other side the entry of contaminants such as dust is prevented by the provision of the rings 32 and 33 which therefore protect the components 17, 18 and 19 of the bearing.

In accordancewith the invention, the circumference of the end wall 14 is provided with circumferentially alternating recesses 42 and projections 43 which are dimensioned so that the recesses 42 can accommodate the projections 41 of the end portion 12, and the projections 43 can enter into and be accommodated in the recesses 40 of the end portionl2 When the roller according to the present invention is to be assembled, the end walls 14 (one shown) are first assembled, that is the components making up the respective end wall 14 are assembled. Of course, if the end walls 14 are not of the type having a bearing incorporated as in the illustrated embodiment, they could conceivably each be of a single piece. To assemble the illustrated embodiment,-however, the bearing components 17, 18 and 19 are first pushed on to the annulus 15 so thatthe nose 21 retains the bearing. Thereafter, the rings 33 and 32 are'put in place and the annulus 26 is placed about the thus assembled components, until the nose 31 projects into the associated abutment of the recess with a snap action and the nose 20 extends behind the ring 28. Now the ring 27 is press fitted into the end portion 12 of the wall 10 and the entire end wall .14 is inserted until the slightly over-dimensioned ring'27 is pressed outwardly by it into tight press-fitting engagement with the inner circumferential surface portion 12 the end portionl2 and the nose 35 of the ring 27 snaps into the associated groove (see FIG. 1) of the annulus 26. The end wall 14 is now firmly fitted into the end portion 12 of the wall 10. g v

The next step in assembly is to rollingly deform the projections 41 into the recesses 42, which can be readily accomplished even if the wall thickness of the wall 10 is relatively substantial. It is clear that when this is completed, relative axial movement of the end wall l4 inwardly or outwardly of the circumferential wall 10, or relative circumferential rotational displacement of the walls 10 and 14 is completely impossible. Moreover, it is evident that this impossibility will continue even if the rolleris used in continuous operation, subjected to high stresses and substantial temperature fluctuations, because of the tooth-like inter-engagement of the recesses 40 with the projections 43 and of the recesses 42 with the projections 41.

It will be appreciated that instead of the three recesses 40 and projections 41, with a corresponding number of recesses and projections provided on the end wall 14, a different number of recesses and projections can be provided on the walls 10 and 14. Similarly, the circumferential dimension or length of recesses and projections need not be identical, as is illustrated. However, this latter feature does tend to simplify the assembly of the components and is therefore advantageous.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a tubular roller, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

I claim:

1. A tubular roller, particularly for conveyors and the like, comprising a tubular wall having opposite end portions and being provided at the latter with circumferentially alternating first recesses and first projections; and end walls rigidly connected with said tubular wall at said end portions, each of said end walls including a first section of substantially annular configuration accommodated interiorly of said tubular wall and inwardly of the respective first recesses, and each of said end walls also including a second section provided with circumferentially alternating second recesses and second projections, each of said first projections being received by and substantially filling one of said second recesses, and each of said second projections being received by and substantially filling one of said first recesses.

2. A tubular roller as defined in claim 1, wherein said end portions have surfaces each of which is disposed between a first recess and a neighboring first projection, said surfaces being located in planes extending at least substantially radially of said tubular wall.

3. A tubular roller as defined in claim 1, each of said second sections having an outwardly directed face; and wherein each of said first projections comprises a portion extending inwardly in substantially radial direction of said tubular wall and having an outwardly directed surface which is substantially flush with the outwardly directed face of the respective second section at least in the region of the respective second recess.

4. A tubular roller as defined in claim 1, said tubular wall having an inner circumferential surface, and said first section having an outer circumferential surface, and wherein said inner and outer circumferential surfaces frictionally engage one another.

5. A tubular roller as defined in claim 1, wherein said end walls consist at least in part of synthetic resin.

6. A tubular roller as defined in claim 1, wherein at least said tubular wall is of metallic material.

7. A tubular roller as defined in claim 1, wherein the dimensions of said recesses and projections in circumferential direction of the respective walls are substantially identical.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,793,689 Dated Februar)" 1974 Inventor(s) DIETER SPECHT It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below: I

On the cover sheet [19] "Specth" should read Specht -v Also on the cover sheet [75]., "Dieter Specth" should read Dieter Specht Signedandjsealed this 13th day of Au gustl974.

(SEAL) Attest:

MCCOY M. GIBSON, JR.- c. MARSHALL DANN Attesting Officer l 4 Commissioner of Patents F ORM PO-1050 (O-69) 

1. A tubular roller, particularly for conveyors and the like, comprising a tubular wall having opposite end portions and being provided at the latTer with circumferentially alternating first recesses and first projections; and end walls rigidly connected with said tubular wall at said end portions, each of said end walls including a first section of substantially annular configuration accommodated interiorly of said tubular wall and inwardly of the respective first recesses, and each of said end walls also including a second section provided with circumferentially alternating second recesses and second projections, each of said first projections being received by and substantially filling one of said second recesses, and each of said second projections being received by and substantially filling one of said first recesses.
 2. A tubular roller as defined in claim 1, wherein said end portions have surfaces each of which is disposed between a first recess and a neighboring first projection, said surfaces being located in planes extending at least substantially radially of said tubular wall.
 3. A tubular roller as defined in claim 1, each of said second sections having an outwardly directed face; and wherein each of said first projections comprises a portion extending inwardly in substantially radial direction of said tubular wall and having an outwardly directed surface which is substantially flush with the outwardly directed face of the respective second section at least in the region of the respective second recess.
 4. A tubular roller as defined in claim 1, said tubular wall having an inner circumferential surface, and said first section having an outer circumferential surface, and wherein said inner and outer circumferential surfaces frictionally engage one another.
 5. A tubular roller as defined in claim 1, wherein said end walls consist at least in part of synthetic resin.
 6. A tubular roller as defined in claim 1, wherein at least said tubular wall is of metallic material.
 7. A tubular roller as defined in claim 1, wherein the dimensions of said recesses and projections in circumferential direction of the respective walls are substantially identical. 